Cakbubeting apparatus



H. HELLWEG.

CARBUBETING APPARATUS.

APPLICATION FILED OCT. 1B, 1915. RENEWED FEB. 26. 1919.

Patented Sept. 2, 1919.

2 SHEETS-SHEET1 Fig 2 INVENTOR ATTORNEY) WITNESSES fi /u ww a) "p /W- H. HELLWEG.

CARBURETING APPARATUS.

APPLICATION FILED OCT. 18. 1915. RENEWED FEB. 26. 1919.

1,314,872. Patented Sept. 2,1919.

2 SHEETS-SHEET 2- Fig 4 .WZNESSES INZZZOR ATTORNEY! UNITED STATES PATENT OFFICE.

HENRY HELLWEG, OF MILWAUKEE, WISCONSIN.

CARB'URETING APPARATUS.

Specification of Letters Patent.

Patented Sept. 2, 1919.

Application filed October 18, 1915, Serial No. 56,412. Renewed February 26, 1919. SeriaLNo. 279,411.

T 0 all whom it may concern:

Be it known that I, HENRY HELLWEG, a citizen of the United States, residing at Milwaukee, cOunty of Milwaukee, and State of Wisconsin, have invented new and useful Improvements in Carbureting Apparatus, of which the following is a specification.

, My invention relates to improvements in carbureting apparatus for internal combustion engines.

The objects of my invention are to provide improved means for regulating the proportionate quantities of air and liquid uel and subsequently regulating the condition without changing the proportions of the mixture admitted to the engine under the varying conditions of service, and also to provide improved means for utllizing the so called heavy or comparatively non volatile hydrocarbon liquids, such, for example, as kerosene, in place of gasolene or naphtha.

M invention is predicated in part upon the discovery that in utilizing heavy hydrocarbon fuels, it is of, great importance to proper regulation, that the proportions of air and fuel be fully determined before any effort is made toward a vaporization of the fuel or toward the heating thereof, preparatory to its delivery to the engine. In my construction the mixture, after its proportions have been fully determined, may be heated and the fuel more fully atomized without danger of affecting the character of the mixture so far as the question of proportion is concerned, as is the case in devices where air is added to the mixture after it has passed the throttle valve in the carbureter on its way to the engine, and after it has been preheated, prior to its delivery to the engine.

When an internal combustion engine-is running slowly, the vacuum created in the carbureting chamber will be comparatively slight, if air is freely admitted to the carbureter. Therefore if the inlet port through which air enters the carburetor is fully open, this vacuum in the'carbureter will not be great enough to cause the discharge of a sufficient quantity of liquid fuel to produce a pro or mixture. For this reason it is desira le that the spring which closes the air inlet valve against the suction of the engine piston, should have sufficient tension to hold the Valve nearly closed under such condi-' tions. But I have found that ordinary spring actuated valves inwhich the 'l'SISiB ance is sufficient to hold. the valve nearly closed under light suction, do not open far enough when the speed of the motor increases, for the reason that the spring resistance in ordinary valves increases with the compression of the spring to a point where it effectively resists the suction pull with the valve only partially open. The engine therefore does not receive an adequate supply of air when running rapidly. One object of my invention is therefore to devise a valve which will be resiliently pressed toward its. seat with sufficient force to prevent the valve from opening too widely at slow speeds, and yet will permit the valve to open more widely without unduly increasing such resistance, thereby attaining the broader object stated in the preceding paragraph of securing before the mixture leaves the carbureting chamber a proper regulation of the proportionate quantities .of air and liquid fuel under varying conditions of service and for various fuels. I

But when the engine is running slowly, the suction which draws the mixture through the carbureter into the combustion chambers is not great enough in ordinary carbureters to properly atomize the fuel since it must be very finely divided in order to prevent its condensation and precipitation, when moving slowly. I therefore provide 'means for additionally breaking up the liquid particles of the charge subsequently to its leaving the carburetor chamber and for utilizing heat to prevent condensation and precipitation upon the surfaces against which the liquid particles are forcibly driven. I find, however, that the particles of fuel cannot be thus heated without also heating the air, which then expands and correspondingly reduces the quantity of air' contained in a given space. When the speed of the engine is slow, the volume of the mixture is not altered sufficiently to prevent a satisfactory action of the engine, but at higher speeds, the expansion of the pre-heated mixture will reduce the quantity admitted to the cylinder or cylinders below the requirements of the engine. I therefore find that it is desirable to deliver the mixture to the cylinder at a lower temperature when running at a higlr speed (or under heav load) than when running at a low spec (ornno load), and I have also discovered thatthe need of preheating preparator} to the delivery of the mixture to: the engine or its manifold is not so great when the engine is running at high speed, because the increased speed. of the current of mixed air and hydrocarbon under such conditions tends. to prevent precipltation not only by reason of increased velocity and consequent inertia, but also by increasing the efiiciency of the atomizing means. My improved regulating means therefore contemplates heating the mixture in mverse proportion to the speed andload of the en- 01116.

6 My invention contemplates not only providing for the admissiomof air to the carbureter more freely than has heretofore been accomplished when the engine is running at high speed and thereby securing, under the varying conditions of speed or load of the engine, a mixture of proper proportions of fuel and air before it leaves the carbureting chamber, but it also provides means for utilizing the exhaust gases from the engine to subsequently pre-heat a portion of the charge after it has left the carburetmg chamber-under conditions adapted to maintain a substantially constant temperature in the heating surfaces, the relative proportion of the charge passing suchheating surfaces,

however, being varied in inverse proportion to the speed of the engine, so that when running at high speed, (or under load, with throttle open), a large portion of the charge will be delivered to the engine without being exposed to said heated surfaces and under such conditions that only a slight degree of heat is imarted to the charge. portion of the charge is preferably surrounded by a quantity of the more highly heated combustible, which has been delivered along said heated surfaces and which of course mixes with the cooler portion of the charge as it enters the engine cylinder, or its manifold. The degree of heat imparted to the mixture depends on four factors, viz: the heat of the walls. the velocity of the mixture, the density of the mixture, and the percentage of the mixture'delivered through the more highly heated passages. By my invention, I control the density and velocity of the mixture in addition to heating that portion of the mixture flowing through the outer passages and during this entire process I maintain substantially the same proportion of fuel and air as originally produced in the carbureting chamber. And by increasing the total area of the ducts through which the carbureted air passes, after leaving the carbureting chamber on its way tothe manifold of the engine, when the engine runs at high speed or heavy load, and decreasing the total area, when the engine runs slowly or at light load, I prevent undue expansion of the carbureted mixture under such conditions and maintain substantially unlform density of the mixture under all conditions of service.

This cooler In the drawings Figure 1 is an elevation of a carbureting apparatus emlbodying my invention.

Fig. 2 is a sectional view, drawn generally on line 2-2' of Fig. 1.

Fig. 3 is a central vertical sectional view of the supplemental heating and mixing chamber, drawn on line 3-3 of Fig. 2,

Fig. 4 is a similar view, drawn generally on the line 44 of Fig. 5 and in which a modified construction of the heating and mixing chamber is shown in connection with a carbureter provided with a plurality of air inlets.

Fig. 5 is a sectional view of the. same drawn on the line 55 of Fig. 4. v Fig. 6 is a detail sectional view of the valved heat controlling fittingemployed in connection with the exhaust pipe, drawn on line 6-6 of Fig. 7 r

Fig. 7 isa plan view of the same.

Like parts are identified by the same reference characters throughout the several views,

Referring to Fig. 1, A designates a carbureter having an extra float chamber B and designed for using two kinds of fuel,'such as gasolene and kerosene, and C designates an intake manifold, all of the usual or any ordinary construction, but I interpose between the carbureter A and manifold C, a supplemental chamber 1 which, for convenience in description, I term a heating and mixing chamber. This chamber is 10- cated' directly above an ordinary throttle.

valve D which is operated by means of the lever E. The chamber 1 is subdivided to form an annular jacket cavity 3 \which encircles a cylindrical plug or member 4,

the lower end of which is tapered conically.

to form a spreader c0ne'5. A series of ducts or passages 6 extends upwardly through the member 4 from the lower portion or receiving cavity 7 to an upper cavity 8 which is capped by a valve "9, said valve, when open, affording communication between the cavity 8 and the outlet cavity 10, whereby fluid may pass, when valve 9 is open, from .the receiving cavity 7 through the ducts 6 through the annular cavity 3 directly to the outlet cavity 10 and at their inlet ends these ducts are partially plugged to provide re?v 1 1 stricted ports 18 through-which fluid enters the ducts from the bottom and is permitted to expand within the ducts. Each of the ducts 6 and 17 is provided with interior projections or flanges, preferably formed by threading the interior wall of the duct for a portion or all of its length, whereby particles of hydrocarbon traversing the ducts are broken up by impact with these projections. The projections in the outer Series of ducts 17 perform the double function of causing the particles of hydrocarbon to be broken up or additionally atomized by impact and'of serving as heat radiating projections which not only give up heat to the hydrocarbon particles in contact therewith, but also to the air passing through these ducts. Y I

The Walls of the ducts 17 are heated by deflecting a portion of the exhaust gases from the engine through the annular cavity 3. To accomplish this, I interpose a fitting 20. between sections of the exhaust pipe 21.

This fitting 20 has a main passage 23 for the normal delivery of exhaust gases through pipe 21, but it is also rovided with 4 branches 25, 26.. A gate va ve 27 is employed to deflect any desired portion of the exhaust gases into the branch from which it is led by duct 29 to the annular; cavity 3, from which it returns to exhaust'pipe 21 through duct 30.. The annular cavity 3 has a partition31 between the ports to which .ducts 29 and arerespectlvely connected as shown in -2 and the heated exhaust gases are therefore required to' circulate about the cavity 3 in passing from one duct to the other. A deflector 33 directs gas from branch 26 of the fitting toward the outlet ofexhaust pipe 21, and a manually adjustable controlling 'valve 40 is adapted to cooperate. with the valve 27 in regulating the exhaust gas delivery.

When the valve 40 is closed, all of.the exhaust gas from the engine is directed through the cavity 3. But when the valve 40 is open, gate valve 27 will be intermittingly opened under the pressure or impact of the exhaust gases, thereby permitting a portion of the gas to follow the pipe 21.

The pivot pin'or pintle 41 upon which valve 27 is hung, is provided with an exterior arm 42. This arm is connected by a curvedlink 43 with a tension'spring 44,- the other end of the spring being connected with the fitting, The spring therefore tends to hold valve 27 to itsseat with the lower end. of link 43 bearing against a stud 46. It will of course be understoodthat valve 40 maybe also actuatd to closed position by a spring and that, it may be manually adjusted to be either .wholly or partially open.

When partially open, the back pressuredeveloped between the valves tends to limit; 6. the opening movements of valve 27. 8.

To properly regulate the volume of air to pin 58 connecting lin secure an adequate supply at full speed and load without unduly diluting the charge for light loads or no load, I employ a valve which is normally held to its seat by a tension spring 51 adjustably connected with bracket 52 at one end, the other end being connected with the valve 'by link 53, bell crank 54 and valve stem 55. The bell crank is pivotally supported at 56 by frame arm 57.. One arm of the bell crank is loosely engaged with valve stem 55 and the other arm projects outwardly from the pivot pin 56 in a position to swlng toward the valve stem when the valve opens. When valve 50 is drawn open by engine suction, there is no material increase in the length and hence in the tension of sprin 51, since the pivot 53 with the bell crank, travels in a circular path, substantially crosswise to the line of the spring and toward but not across, a line through pin 56 to the point of connection between spring 51 and screw 59. This reduces the leverage, with consequent reduction in the effective'power of the spring. For this reason, whenever the suction becomes sufficient to open the valve, the latter moves with substantial freedom and uniform constant resistance to full open position and vice versa, the spring merely retaining sufficient tension to cause the valve to close when the suction ceases.

Assuming the engine to be operated under no load or under a light load or at slow speed, the relatively slow movement of the carbureted mixture tends to permit condensation of the hydrocarbon or precipitation of the hydrocarbon in the passages leading to the engine cylinders. Under such conditions, however, the controlling valve 40 in the exhaust pipe may be wholly or nearly closed and in any case the gate valve 27 will not open as widely as when the en- 'tions, the restricted ports 18 or the ducts 17 will be large enough to permit the passage of the entire charge as determined by the degree of opening or adjustment of the throttle valve. for the throttle valve D will be only partially open. Therefore valve 9 will remain closed and the charge will be drawn through the. ducts 17 of the outer series. The walls of these ducts are in direct contact with the exhaust gases in cavity 3 and the charge is therefore heated to a relatively high temperature and the How will be ac'elerated for this reason and) because the ducts 6 of the inner series are closed.

The entir'e'charg'e therefore passes through ducts of theouter series where it is heated to a relatively high temperature, and the acceleration of the flow increases the force thrown outwardly 'livered through the manifold, is

"trol by manipulation of the valve 40.

or impact of theparticles of hydro-carbon upon the projections contained in the ducts 17. The helical or screw thread form of the projections provides means for setting up a whirling motion in the air currents, whereby the particles of hydro-carbon are by centrifugal force and driven still more forcibly and in larger quantity against the projections.

Assume now that the load is increased and throttle valve D openedto increase the volume of the charge delivered to the cylinders. The ports 18 or ducts 17 not being large enough to permit the passage of the increased charge, valve 9 will open'due to the difference in pressure above and below it and as regulated by the throttle valve. When valve 9 opens, the flow is increased. That portion of the charge which passes through the ducts 6 of the inner series will not be heated to any great extent, and sincethese ducts oifer less resistance to the passage of the air and hydrocarbon, it is ob- .vious that a considerable portion of the charge may be drawn to the engine cylinder through them. The relative proportion passing through ducts 6 and 17 will depend largely upon the speed or load of the engine, the degree to which the throttle valve has been opened, and the extent to which the valve 9 is opened. But wherea full charge is delivered, the heat evolved by compression in the engine cylinder is greater and the speed of delivery to the cylinder being also greater, the opportunity for condensation and precipitation is correspondingly reduced. I am thus enabled to maintain substantially uniform conditions in the cylinder so far as the character of the charge or proportion of air to hydro-carbon is concerned, regardless of the speed and load of the engine.

The temperature of the charge as denot only reduced in the manner above described when valve 9'is opened, but'it is also relatively further reduced whenever such conditions are maintained for any considerable period, since the supply of heat is partially cut ofi by the direct delivery of a greater or less proportion of the exhaust gases through the pipe 21, this, however, being subject to con- I. attach. considerable importance to the fact that the tension of the spring 51 is not materially increased when the air inletvalve 50 is opened, since I am therefore enabled to exactly regulate the tension of spring 51 andby keeping the same at uniform tension, or substantially so, I secure a greater and a more correct proportion of air at high speed or under load, than has been secured with the carbureting apparatus as heretofore'constructed. This is of added importance ,where heavy hydrocarbons are employ'edgsince otherwise the mixture result.

relatively enriched at high speed or load due to the fact that the effective power of "the spring progressively increases as the air inlet valve opens in carbureters as heretofore constructed. Owing to the fact'that the efl'ective power of the spring is reduced" as the pivot 58 swings toward a line through pivot pin 56 and the point of connection between spring 51 and screw 59, the resistance to the opening movement of valve 50 is "not only reduced, but the valve ends to remain open for a longer period, its movement being sluggish when adjacent to itsifully open position. The amount of air in the charge is therefore larger and the charge is larger and compression greater'than would otherwise be the case. Further, a sudden closing of the throttle valve'is not followed by an instant closing ofthe air inlet-valve with consequent undue enrichment of the mixture due to the inertia of the liquid fuel, and correspondingly, a sudden opening of the throttle valve is not followed by an immediate opening of the air inlet valve before the inertia of the-liquid fuel can be overcome.

It will be observed that the motion of the regulating-valve 27 is controlled in the. same manner as above described with reference to the air inlet valve. With this construction, the valve 27 may open fully and remain open when the engine is running at high speed or full load, thus avoiding the hammering eifect, which would otherwise The valve 27 becomes efi'ective how ever as soon as the force of the exhaust or the rapidity of the discharges becomes reduced to'a point where it is desirable to increase the proportionate quantity of such gases to be deflected to the heating chamber. Referring now to the modified structure illustrated in Figs. 4 and 5, it will be observed that the same reference characters are applied to the like parts illustrated in Figs. 1, 2 and 3, but where the structure of such parts is modified, the 1 reference character a is added. I 17In Figs. 4 and 5 the Walls of the ducts the plug or member 4 in which the ducts 6 which are shown as integral with they outer wall of the chamber '1, and the plug are formed is exposed to the heated gas. in

the passage 3 and the fluid mixture passing through said ducts is thus more or less heated. v

In the construction shown in Figs. 1,2 and ner wall or the cavity or passage3, a closed 3 between the plug or member 4 and the inannular insulating cavity '61. is formed, 1

which tends to prevent conduction of heat from said cavity or passage to the ducts 6. However, the inner cavity or passage 61 or 3*" may be altogether omitted, or, if used,

may be closed or open to the circulation of closing said valve 65 is the same as that above described for closing the valve 50, the same reference characters being applied. Theauxiliary air valve 65 shown in Fig. 4, however, permits an admission of air to the uppefportion of the carbureter below the throttle valve.

I attach great importance to the fact that in my improved carbureting apparatus the proportion of combustible to be exposed to the highly heated surfaces is regulated according to the requirements of the engine, since by so doing the degree of heat is accurately controlled and kept from becoming so excessive as to lower the efficiency of the engine at the time when efficiency is most required, viz:--when running under heavy load. In such cases the valve 9 or 9 opens most widely and the charge passes through the ducts at high velocity and is delivered to the cylinder at comparatively low temperature. through the outer set of ducts is additionally diminlshed in temperature only by reason of its increased velocity and as it becomes considerably heated, it is effective to keep thetop wall of cavity 10 or 10" warm and to largely prevent contact of the cooler portions of the charge therewith. The valve 27 in the exhaust pipe opens more widely in proportion to the increased force of the exhaust and this prevents any increase in the heating effect of these gases upon the ducts 17. l

It will also be observed that the throttle valve is interposed between the carbureting chamber and the heating and mixing chamber, thereby not only'controlling the volume of combustible delivered to the heating and mixing chamber,- but also xcontrollin its density in such chamber. This is done in cooperation with the valve 9 which intermittingly closes the central passages and progressively lengthens the closing periods whenever the speed of the engine decreases or the closing of the throttle valve tends to reduce the density of the mixture, thereby maihtaining a more uniform density of that portion of the mixture which passes through the outer set of ducts.

The terms and expressions emplo ed in the foregoing description and in t e appended claims are used for the purpose of descript on and not of limitation, it not be- But the portion which passes ing my intention to exclude from the scope of my invention any mechanism equivalent for the parts and combination of parts illustrated and described. 1

, I have thus provided means for regulating the proportionate quantities of fuel and air before the charge leaves the carbureting chamber and for successfully effecting subsequently a partial vaporization of the hydrocarbon by passing'a portion of the carbureted mixture over heated surfaces and simultaneously effecting an "additional atomization of the liquid particles without changing the proportions of fuel and air as originally produced in the carbureting chamber, the heat being kept substantially constant but the proportionate volume of the mixture being varied under varying conditions, and in so doing I also provide means for maintaining a suitable velocity of the combustible mixture in its passage to the enginecylinder and particularly in its passage through the heating and atomizing chambers or passages, the capacity of which is varied under varying conditions of speed or load and in correspondence with the requirements of any given condition. I also provide means whereby the carbureted mixture may be heated without danger of overheating or heating the mixture to a point Where the operation of the engine will be impaired, and in which means the expansion of the explosive mixture is controlled to meet the varying requirements of the engine.

I claim 1. In a carbureting mechanism for internal combustion engines, the combination with the engine manifold, of a carbureting chamber, an auxiliary chamber interposed between the carbureting chamber and the and means for heating the mixture while passing through said passages.

2. In a carbureting mechanism, a heating and mixing chamber provided with a plurality of passages, unobstructed in their central portions, means for heating the walls of some of said passages above the temperature of the others, and means for directing carbureted air through said passages in "whirling currents, whereby the particles of hydrocarbon are thrown against said walls; said passages being numerous and of sufiiciently small diameter to expose substantially all the particles of hydrocarbon to contact with the walls.

3. In a carbureting mechanism, a heating and mixing chamber provided with afplurality of passages unobstructed in their central portions, means for heating the walls of some of said passages above the temperature of the others, and means for directingsmall diameter to allow substantially all unvaporized hydrocarbon to be exposed to impact against Y said pro ections.

4. In a carbureting mechanism for internal combustion engines, a heating and mix-- ing chamber provided with a plurality of passages, leading in common from-the inlet to the outlet portion of said chamber, and means fordelivering carbureted air to the inlet portion of said chamber, in combination with means for normally closing some of said passages, and means for opening said normally closed passages under predetermined condition of relative pressure in the respective end portions of said chamber.

5. In a carbureting apparatus, the combination with a-carbureter for producing a preliminary combust'ble mixture of liquid fuel and air, of a supplemental heating and mixing device connected with the outlet of the carbureter and comprising means for heating a portion of the mixture to a higher temperature than that of the remaining portion passingthrough the device, means for increasing'and decreasing the total quantity of the mixture delivered to said heating and mixing device in accordance with the speed and load of the engine, and means for automatically increasing and decreasing the percentage of the more highly heated portion ofthe mixture inversely to the total quantity delivered.

6.- In a carbureting mechanism for internal combustion engines, a heating and mixing chamber provided with a spreading cone having an inner series of valve controlled passages extending therethrough and also having an outer series of passages lead ing upwardly through said chamber from the outer margin of the cone,said chamber having a cavity extending along the Walls of said last mentioned passages,an engine exhaust pipe, and a branch connection there for leading to said cavity.

7. In a carburetmg mechanismfor internal combustion engines, a heating and mixing chamber provided with a spread-' ing cone having an inner series of valve controlled passages extending therethrough and also having an outer series of passages leadthrough said chamber from the outer margins of the cone,said chamber having a cavity extending along the walls of said last mentioned passagcs,-an'

engine exhaust pipe, tion therefor leading to said. cavity, and means for regulating the proportion of exhaust gases passing through said branch connection in inverseproportion to the total quantity of the exhaust gases.

8. In a carbureting mechanism, the .combination witha carbureting chamber, of a heating and mixing chamber, connected with the carbureting chamber and adapted to receive combustible fluid therefrom, said heating and mixing chamber being subdivided into a plurality of passages leadingin common from the inlet to the outlet portion of said chamber, means, dependent upon the quantity of fluid delivered to the heating and mixing chamber, for closing some of said passages independently of the others, and means for heating thewalls of the remaining passages to a higher temperature.

9. In a carbureting mechanism, a heating and mixing chamber, in combination with means for delivering a combustible fluid thereto, said chamber having inlet and outlet portions, and being subdivided, intermediate thereof, into a plurality of passages leading in common front the inlet to the outlet portions, and means for maintaining the walls of some of said passages at a higher-temperature than the others, together with yieldingly opposing the passage of and a branch connecfluid through the less highly heated pasthe carbureted mixture may be maintained at substantially uniform velocity and density in the constantly open duct.

11. In carburetmg apparatus, the combination of a carbureter provided with an automatic air inlet valve having a substantially uniform and constant yielding resistance to its opening movement for producing a preliminary mixture offuel and air, an auxiliary mixing device comprisingducts for the mixture, one of which is constantly open, means for automatically opening and closing the other duct according to the varying demand for the mixture, means for heating the constantly open duct to a higher temperature than that of the other; said automatic air inlet valve being adapted to cooperate with the means for opening and closinga portion of the auxiliary mixing device and preserving substantially uniform heating effects in the constantly open portion.

12. A carbureter outlet, including means for automatically subdividing the carbureted mixture and subsequently reuniting the same, in combination with means dependent on the speed and load of the engine for heating one portion of the subdivided mixture to a higher temperature than the other portion.

13. A carbureter outlet, including auxiliary heating means adapted for heating a portion of the carbureted mixture to a higher temperature than the remainder, in combination with means for varying the percentage of the more highly heated portion to the remainder in correspondence with the quantity of the charge as delivered to .the engine under varying conditions of speed and load.

14. In carbureting apparatus, a heating and mixing device comprising ducts for a carbureted mixture, one of which is constantly open, means for independently opening and closing the other duct according to the varying demand for the mixture, and means for heating the walls of the constantly open duct to a higher temperature than that of the other duct.

15. In carbureting apparatus the combination with a carbureter for producing a preliminary mixture of fuel and air, of an auxiliary mixing device provided with ducts for the mixture, one of which is constantly open, and means for opening and closing the other duct according to the varyin demand for the mixture.

n testimony whereof I aflix my signature in the presence of two witnesses' HENRY HELLWEG.

Witnesses:

LEvEnETT C. WHEELER, IRMA D. BREMER. 

